气候变化领域集成服务门户(CCPortal): Modeling the Dynamics of Small-Scale River and Creek Plumes in Tidal Waters

CCPortal

DOI	10.1029/2019JC015737
	Modeling the Dynamics of Small-Scale River and Creek Plumes in Tidal Waters
	Basdurak N.B.; Largier J.L.; Nidzieko N.J.
发表日期	2020
ISSN	21699275
卷号	125 期号:7
英文摘要	The fate of discharges from small rivers and mountainous streams are little studied relative to the dynamics of large river plumes. Flows from small watersheds are episodic, forming transient low-salinity surface plumes that vary tidally due to interaction of outflow inertia with buoyancy and ambient tidal currents. An implementation of the Regional Ocean Modeling System (ROMS v3.0), a three-dimensional, free-surface, terrain-following numerical model, is applied to small river outflows (≤10 m3 s−1) entering a tidal ocean, where they form small plumes of scale ~103 m or smaller. Analysis of the momentum balance points to three distinct zones: (i) an inertia-driven near field, where advection, pressure gradient, and vertical stress divergence control the plume dynamics, (ii) a buoyancy-driven midfield, where pressure gradient, lateral stress divergence, and rotational accelerations are dominant, and (iii) an advective far field, where local accelerations induced by ambient tidal currents determine the fate of the river/estuarine discharge. The response of these small tidal plumes to different buoyancy forcing and outflow rate is explored. With increasing buoyancy, plumes change from narrow/elongated, bottom-attached flows to radially expanding, surface-layer flows. Weak outflow promotes stratification within the plume layer, and with stronger outflow, the plume layer becomes thinner and well-mixed. When compared with prototypical large-river plumes in which Coriolis effects are important, (i) in these small plumes, there is no bulge and no coastal buoyancy current, that is, shore contact is mostly absent, and (ii) the plume is strongly influenced by ambient tidal currents, forming a tidal plume that is deflected upcoast/downcoast from the river mouth. ©2020. American Geophysical Union. All Rights Reserved.
英文关键词	river plumes, small-scale, model, dynamics, tidal
语种	英语
来源期刊	Journal of Geophysical Research: Oceans
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/186804
作者单位	Bodega Marine Laboratory, University of California, Davis, CA, United States; Now at Leibniz Institute for Baltic Sea Research Warnemünde, Rostock, Germany; Coastal and Marine Sciences Institute, University of California, Bodega Bay, CA, United States; Department of Environmental Science and Policy, University of California, Davis, CA, United States; Department of Geography, University of California, Santa Barbara, CA, United States
推荐引用方式 GB/T 7714	Basdurak N.B.,Largier J.L.,Nidzieko N.J.. Modeling the Dynamics of Small-Scale River and Creek Plumes in Tidal Waters[J],2020,125(7).
APA	Basdurak N.B.,Largier J.L.,&Nidzieko N.J..(2020).Modeling the Dynamics of Small-Scale River and Creek Plumes in Tidal Waters.Journal of Geophysical Research: Oceans,125(7).
MLA	Basdurak N.B.,et al."Modeling the Dynamics of Small-Scale River and Creek Plumes in Tidal Waters".Journal of Geophysical Research: Oceans 125.7(2020).